Vapor heating system



Dec. 3, 1946.

A. F. HOESEL I VAPOR HEATING SYSTEM Filed July 10, 1944 I INl Z/VTOR Patented Dec. 3, 1946 VAPOR HEATING SYSTEM Anthony F. Hoesel, Chicago, Ill'., assignorto Peerless of America Inc., Chicago, 111;,

of Illinoisa corporation Application July 10, 1944-, Serial No; 544,306

6 Claims.

The present invention. relates to vapor heating systems and especially relates to such systems wherebythe heating ofthe vapor is accomplished by waste heat such as is rejected in the exhaust discharge of an-internalcombustion engine.

One of the advantages of my invention is that the maximum vapor pressure is automatically controlled to some predetermined point, irrespective of the amount and/or intensity of the heat generating the vapor and also irrespective of the amounttof vapor condensed by means of rejecting its heat to some other medium of a lower temperature than that of the vapor temperature.

Because of the controlled pressures, it is possibleto use vapor generators (generally called boilers), vapor condensers (generally called radiators) and connectingvapor conduit means of aconsiderably-lighter construction than thatused in conventional systems of-the vaporpressure In view of the fact that the vapor pressure is automatically controlled, I .find it possible, to dispense with the usual'selfseating type safety valve.

Another advantage stems from the iact that mysystem is completelyplosed and, while. in a cold state, is under a partial vacuum, which decreases the boiling point temperature, ofv the contained liquid-, so thatthe transfer of'heat begins rather rapidly when the system starts up.

Since many'systems of thistype, have to withstand sub-freezing temperatures, my closedsystem has the advantage of preventing theescape or any anti-freeze flu-id having a lowboiling point. In the drawing:- Fig. 1 is an elevationalview of a heating.- system embodying- Ethe invention.

Fig-2 is an. elevational view, partly in crosssectiornof a. pressure-control used in the system Fig.. 1.

Fig; 3 is a cross-sectional view-along; line 3-3 An exhaust pipe 6- connects to the manifold 5,.

as indicated, and serves tocarry the hot exhaust gases to a. muffler, not shown.

It should be particularly noted that the exhaust pipefi hasa downwardly leading portion 1 which shall be referred. to later. Around the portion 1., I mount a shell 8, which, being of greater inside diameter than the'outside diameter of the portion 1, provides an annular-space 9, which, during normal operation, is at least partly filled with. the vapor generating liquid. Both ends, 10 and H, of the shell 8, are. hermetically sealed, by weldingror otherwise, to the exhaust pipe portion if The immediate above comprises the vapor generator.

At I2 I indicate a vapor condenser comprising, a vapor header I3 having vapor tubes l4 'upon which are mounted fins 15' in order to increasethe effective heat transfer area I A motor I6, driving the fan ll, serves to blow air over the exterior surfaces of the tubes l4 and fins l5 therebyheating such air andcondensingvapor within the tubes M.

The tubes l4drain into a condensate collector lsirom the bottom of which projects a condensate return conduit IQconnected to the low end ofthev shell .8 as indicated. Immediately below its connection, to the shell 8, the condensatereturn. conduit l9 is provided with a liquid trap 20.

The upper end, of the shell 8, is provided with a vapor conduit 2| leading to the inlet 22 of the pressure control 23 whose outlet 24 is connected to'the vapor header I3 by means of the conduit 25.

The vapor condenser l2 isprovided with a filler capi26' whereby thelsystem may be charged with a definite quantity of vaporizable liquid. This quantityis generally slightly, in excess of that which willfill the annular'space 9.

In Fig. 2, the pressure control 23 comprises a body 21having a vapor inlet'22 'and'vapor outlet 24 between which isa valved passage 28'having a. seat 29 cooperative with the valve 33 having a guide portion 3] which plays in'the bore 32 of the cap 33 threadedly engaging the bore '3401 the body I 21.

The valve 30, constantly urged to the valve seat 29 by means of the spring 35, has a stem 36 pressing against a. diaphragm 31, which is hermetically sealed to the body 2'! and the diaphragm cover 38 as indicated at 39.

The diaphragm cover 38 has a breather hole Ml and athreadedbore 4| in the latter of which an adjusting screw .42 serves to put a proper pressure upon the diaphragm spring 43, mounted up'onthe diaphragm pusher disc 44, thereby tending to move thevalve'30 away from itsjseat 29.

Having described the various elements jofl the system, I shall now describe its operation. Assume thatthe pressures, 'oi'the springs .35 and 43, are of sucnvalues' that a gagepressure of say 4 p. s. i., at the outlet 24, results in the diaphragm 31 moving downwardly and the valve 30 engaging the seat 29. Further assume that the valve 30 is in open position, as shown, at 1 p. s. i. and has an increased throttling action with increase 'of pressure until 4 p. s. i. is reached at which time the valved passage 29 is completely closed.

We now remove the filler cap 26 and pour in a definite quantity of liquid. The annular space 9 is practically filled and the liquid extends up into the condensate return conduit 19 to approximately the level 48. We now start the source of heat; The liquid, in the annular space 9, starts to boil and vapor issues from the hole in which the filler cap 28 screws. The vapor tends to drive out the air in the system and after a sufiicient period of time we replace the filler cap 26. The system is now pressure tight.

During various operations, the vapor condenser I2 will have difierent condensing capacities. If the motor I6 is stopped then the condensing capacity is at a minimum. If the motor I 6 is in operation and the entering air is cold, then the condensing capacity will be at a maximum. Between these two extremes there will be numerous variations in condensing capacity.

During the operation, of the engine rejecting heat to the exhaust manifold there will be varying volumes and heat intensities of the exhaust gasespassing through the exhaust pipe 6. Since the amount of heat transfer surface, of the portion I, is constant, the potential vaporizing capacity thereof will vary accordingly and the actual vaporizing capacity will be a function of both the amount of surface area, of the portion I, wetted by the vaporizing liquid and the volume and heat intensity of the exhaust gases passing therethrough.

Let us assume a static condition of operation wherein a certain constant exhaust discharge heats the liquid sufi'iciently to maintain a constant vapor pressure of 1 p. s. i. in the vapor conduit2l. The valve 30 is in the wide open position and the vapor condenser I2 is assumed to reject heat at the same ratethat it is generated.

Obviously the vapor flow, through the conduit 2|, the pressure control 23, the conduit 25 and the vapor condenser I2, involves a pressure drop. Let us assume that this pressure drop is on the order of 3." water. Under this condition we find that the static liquid level 48 will change to liquid level 49, which presumably is 3 higher than previously.

There now exists a differential of 3 in the liquid levels of the annular space 9 and the condensate return conduit [9.

Let us now suppose that the air, passed over the vapor condense l2, has increased in temperature and/or decreased in volume. Obviously its heat absorption capacity is decreased and the generated vapor pressure tends to increase. The valve 30moves towards its seat 29, thereby increasing the flow pressure drop, and the liquid level rises to point 50 of the condensate return conduit l9.

Of course, as the liquid recedes into the condensate return conduit [9, the liquid level lowers in the annular space 9 and with the consequent decreased wetted surface, of the portion 1, the vaporizing .capacity is reduced accordingly and automatically to the condensing capacity of the vapor condenser l2.

7 Assuming a condition of no heat demand, on the part of the vapor condenser l 2, and a passage of maximum volume and heat intensity, of exa constantly open'condensate return conduit be- 4 haust gases, through the exhaust pipe 6. We would find that the vapor pressure would quickly rise to 4 p. s. i. and that the valve 30 would be seated. Under this condition the entire liquid volume, in the annular space 9, tends to recede into the condensate return conduit 19 and the condensate collector [8. Since the wetted surface, of portion 1, is practically zero,. there can be no further generation of vapor.

As explained previously, the header I3 and the tubes I4 are filled with vapor and, as soon as sufficient vapor condenses. the 4 p. s. 1. pressure drops. Since the diaphragm 31 is subject to the pressure, obtaining. in the vapor header I3, a drop in the pressure-from the previous 4 p. s.'i.-- allows the diaphragm 31 to push the valve 30 away from its seat 29 thereby reestablishing a throttled vapor flow, which is accompanied by some liquid again. entering the annular space 9 and wetting sufiicient of the exhaust pipe, portion 1, to maintain a pressure of somewhat less than 4 p. s. i. and more-than 1 p. s. i.

Whenever the system is at rest, it tends to arrive at ambient temperatures, which are considerably lower than the boiling point of the liquid, consequently the previously generated vapor condenses and produces a partial vacuum within the system. To clearly illustrate the advantage of this, let us assume the liquid to be water and the vacuum to be 20 inches mercury. The boiling point of water, at atmospheric pressure, is 212 R, and this temperature must be reached before effective heat transfer vapor (steam in this case) can be forced through a conventional (steam) heating system. With my systemstarting with a 20 inch mercury vacuum -ave find that the boiling point would be F., there fore my system starts to transmit vapor-for the heat transfer purposeat a 52 F. lower temperature. This is conducive to a quick warm up of the space to be heated.

While the specific embodiment of the inven tion is of a preferred form, it is to be understood that there may be various modifications there-- of without departing from the spirit and scope of the invention, which is to be limited only to the hereto appended claims. I claim:

'1. A vapor heating system for a body enclosure:

associated with an internal combustion engine, comprising: an exhaust pipe for the engine, a chamber adapted to contain a body of liquid in its lower portion and to be heated by said pipe, a vapor-condenser disposed above said chamber; for heating the enclosure, a vapor-conduit between the upper portion of said chamber and the upper portion of the condenser, pressure control means in the vapor-conduit for restricting the flow of vapor to the condenser responsively to--an increase of vapor pressure in the vapor-conduit,

tween the lower portion of the condenser and the lower portion of said chamber, the system being sealed against atmosphere and containing a predetermined quantity of liquid.

2. A vapor heating system for a body enclosure associated with an internal combustion engine, comprising: an xhaust pipe for theengine, a chamber adapted to contain a body of liquid in {its lower portion and to be heated by said pipe, a vapor-condenser disposed above saidchamber, for heating the enclosure, a vapor-conduit between the upper portion of said chamber and the upper portion of the condenser, pressure control means in the vapor-conduit for restricting the flow of vapor to the condenser responsively to an increase of vapor pressure in the vaporconduit, a valveless condensate return conduit betwen the lower portion of the condenser and the lower portion of said chamber, the system being sealed against atmosphere and containing a predetermined quantity of liquid.

3. A vapor heating system for a body enclosure associated with an internal combustion engine, comprising: an exhaust pipe for the engine, a chamber surrounding a portion of the exhaust pipe and adapted to contain a body of liquid in its lower portion and to be heated by said pipe, a vapor-condenser disposed above said chamber, for heating the enclosure, a vapor-conduit between the upper portion of said chamber and the upper portion of the condenser, a pressure control valve in the vapor-conduit for restricting the flow of vapor to the condenser responsively to an increase of vapor pressure in the vapor-conduit, a constantly open condensate return conduit between the lower portion of the condenser and the lower portion of said chamber, the system being sealed against atmosphere and containing a predetermined quantity of liquid.

4. A vapor heating system for a body enclosure associated with an internal combustion engine, comprising: an exhaust pipe for the engine, a chamber adapted to contain a body of liquid in its lower portion and to be heated by said pipe, a, vapor-condenser disposed above said chamber for heating the enclosure, a vapor-conduit between the upper portion of said chamber and the upper portion of the condenser, a normally open pressure control valve in the vapor-conduit for restricting the flow of vapor to the condenser responsively to an increase of vapor pressure in the vapor-conduit, a constantly open condensate return conduit between the lower portion of the condenser and the lower portion of said chamber, in the lower portion of which the column of liquid from the chamber is variable in height responsively to variation in pressure in the vapor in the condenser, the system being sealed against atmosphere and containing a predetermined quantity of liquid.

5. A vapor heating system for a body enclosure associated with an internal combustion engine, comprising: an exhaust pipe for the engine, a chamber surrounding the exhaust pipe and adapted to contain a body of liquid in its lower portion and to be heated by said pipe, a vaporcondenser disposed above said chamber for heating the enclosure, a vapor-conduit between the upper portion of said chamber and the upper portion of the condenser, a pressure control valve in the vapor-conduit for restricting the flow of vapor to the condenser responsively to an in crease of vapor pressure in the. vapor conduit, a valveless condensate return conduit between the lower portion of the condenser and the lower portion of said chamber, the lower portion of which includes a trap-portion through which the column of liquid from the chamber is variable responsive to variations in pressure in the vapor in the condenser, the system being sealed against atmosphere and containing a predetermined quantity of liquid.

6. A vapor heating system for a body enclosure associated with an internal combustion engine, comprising: an exhaust-pipe for the engine, a cylindrical chamber surrounding the exhaust-pipe adapted to contain a body of liquid in its lower portion and to be heated by said pipe, a vapor-condenser disposed above said chamber, for heating the enclosure, a'vaporconduit between the upper portion of said chamber and the upper portion of the condenser, pressure control means in the vapor-conduit for restricting the flow of vapor to the condenser responsively to an increase of vapor pressure in the vapor-conduit, a valveless condensate return conduit between the lower portion or the condenser and the lower portion of said chamber, the system being sealed against atmosphere and containing a predetermined quantity of liquid.

ANTHONY F. HOESEL. 

